Drain hose for automatic washing machines and similar devices has previously been made of heavy rubber or neoprene tubing having a rigid 90.degree. or 180.degree. bend in the end of the tubing or having a bent piece of metal tubing inserted in the end of the tubing. The bent portion is inserted in a standpipe to provide an outlet for discharged water. This arrangement has some drawbacks. The heavy rubber or neoprene tubing is expensive and the smooth surface of the neoprene, or the metal, does not maintain firm contact between the drain tubing and the standpipe. As a result, vibration and the water jet action during draining of the machine may lift the tubing out of the standpipe causing the water ejected therefrom to be spread on the basement floor of the user or in the area of use of the machine instead of allowing it to be piped into the sewer.
Recently, molded and extruded corrugated hose has come into use. This hose is made of semi-rigid or flexible plastic and is less expensive than the heavy neoprene hoses. The tubing does not have a permanent bend formed at its exit end, but is normally held in a 180.degree. arc by a wire retainer. The loose end of the hose is inserted into the standpipe. This arrangement also has a number of drawbacks. There is no provision for retaining the hose in the top of the standpipe under the influence of water thrust and vibration during pumping of the water from the machine. In addition the softer flexible hose can be readily damaged from friction which occurs as a result of vibration and movement of the hose in the standpipe. As a result, the hose is often gradually abraded away or crushed.
In small standpipes it may be necessary to cram the corrugated hose forcefully into the top of the standpipe with the result that there is a seal around the upper edge. This is a drawback from a number of standpoints, particularly since it does not allow water on the outside of the hose to drain into the standpipe. This arrangement can also create a siphon effect under some circumstances and water may be drawn through the drain back into the machine.
The standard wire adapter provides no means by which the shape of the bend in the hose can be changed, e.g., from a 180.degree. to a 90.degree. bend, as desired and as the circumstances require.
Applicant has produced an adapter which can readily change the shape of the bend in a corrugated hose from any curvature from a 0.degree. to a 180.degree. position, as desired. The adapter will fit standard molded or extruded corrugated hose, will retain the end of the hose in the adapter and protect the hose from abrasion and crushing, will retain the hose in the standpipe under the influence of vibration and water thrust. The adapter has a wedge fit which provides an adequately tight fit but does not allow the adapter to jam into a standpipe so that it is difficult to withdraw. The adapter is provided with an anti-siphon which allows air to pass between the interior of the standpipe and the exterior of the adapter. The anti-siphon prevents water from the drain or sewer being drawn back into the machine. The air passage also minimizes back pressure caused by air trapped in the drain during expulsion of water into the drain.